In cellular communications systems, a multiplicity of base stations may be distributed throughout a geographical area. Each base station communicates with user equipment (UE) devices, such as cellular phones, for example, which may move throughout the geographical area.
In order for the UE to perform coherent demodulation of the signals that it receives from a base station with which it is currently communicating, the UE needs to perform channel estimation. In order to facilitate channel estimation at the UE side, the base station may periodically broadcast, at known times and/or at known frequencies, “pilot” signals which are known to the UE and may be utilized to acquire the necessary channel information. Pilot signals may also be referred to as “reference signals” (RS), and these terms are used interchangeably throughout the following disclosure.